Post on 13-Jan-2016
Last lesson
• Learning to listen
• Sound as vibrations
• Amplitude and volume
• Frequency and Pitch
• Range of human hearing
Amplitude = volume
Pitch = frequency
Range of hearing
Humans can hear up to a frequency of around 20 000 Hz (20 kHz)
Today’s lesson
• The ear
• The decibel scale
• Hearing loss
The earYouTube - acland's anatomy 1
YouTube - Science of Sound
Can you gather around Mr Porter
please?
Mr Porter has a sheet for you to do
The decibel scale
The sound intensity level attempts to quantify the sensation of hearing. It relates sounds to the lowest intensity that can normally be heard by a human ear (0.000000000001 W.m-2)
Sound intensity level (dB) = 10log(I/Io)
where Io = 1 x 10-12 W.m-2.
Decibel scale
Decibel scale
Damage to hearing
Can you READ page 147 and either brain-map the page or design a poster describing causes of hearing loss.
ADVANCE WARNING
Test on 5th October